seemed like one was in the works before for it when following the Beta/RC versions of 3.1.

No there wasn't one in the works for 3.1. Neither for 3.2, only a conceptual idea. There was a focus on trying to substantially improve prosilver for 3.2 but that was where the limitations of prosilver really came to light.

I like how prosilver looks in 3.2. At first I didn't want to see prosilver be dropped, but now I agree that a new style for 3.3 is the best idea. It does look like there is going to be a new style in phpbb 3.3.